(1) Field of the Invention
The invention relates to a mounting mechanism for a scroll machine, and more particularly to which utilizes a built-in mounting mechanism for lowering down assembly errors and reducing difficulty in assembling.
(2) Description of the Prior Art
A conventional scroll machine or a volute compressor in the art, structured as shown in FIG. 1, comprises mainly a shell 10, a non-orbiting scroll member 24 installed inside the shell 10, an orbiting scroll member 30, and other necessary components. While in meshing of the non-orbiting scroll member 24 and the orbiting scroll member 30, each having continuous individual involute blade, a plurality of closed compression chamber 34 are formed separately between contact lines of blades for accommodating working media (either gas or fluid). Those compression chambers 34 are moving with the contact lines of two blades in operation, and the occupied volume of a compression chamber 34 become less and less as it moves toward center of the scroll member 24 or 30 for obtaining a compressing effect upon the working media confined in the compression chamber 34. Inside the shell, space above the fixed volute is called a high pressure room 18. The inlet of the high pressure room 18 is formed as an axle hole 22 of the neck 26 located along the center of the non-orbiting scroll member 24. The eccentric motion of the orbiting scroll member 30 is driven by a motor 3 located beneath thereof.
Notwithstanding, if position or angular error occur while assembling scroll members 24 and 30 in a conventional scroll machine, it is quite possible that the separation of compression chamber 34 will lose and the working media inside a compression chamber 34 will leak through the slit existing at root or top of the adjacent contact line, and thus the compression capacity of the scroll machine will be greatly reduced. To avoid possible ill-closeness in forming the compression chambers 34, accuracy in producing the relative components and an improved mounting means for the scroll members are two major resorts.
As exemplified by the disclosures in the U.S. Pat. Nos. 4,767,293 and 4,877,382, the non-orbiting scroll member is provided in the back thereof with a biasing piece device which is fastened securely with a frame by means of bolts in conjunction with a locating piece. In the meantime, the biasing piece device is locked with the non-orbiting scroll member by another set of bolts. The non-orbiting scroll member is capable of moving axially. The moving distance of the non-orbiting scroll member is regulated by the interval between the planar surface of the frame holding the non-orbiting scroll member and the planar surface of the frame locking the biasing piece device, as well as the rim thickness of the non-orbiting scroll member. When the working media in the compression chamber has an abnormal pressure, the axial separation force of the compression chamber is greater than the axial sealing force exerting on the back of the non-orbiting scroll member. As a result, a gap is formed between the orbiting scroll member and the non-orbiting scroll member which must overcome the elastic force of the biasing piece by retreating to the planar surface of the biasing piece, which is pressed by the locating piece and is locked with the frame. The prior art improvements described above arc defective in design in that the improvements are attained by means of a number of elements at the expense of manufacturing efficiency and assembly precision.
Another prior art improvement is disclosed in the U.S. Pat. No. 5,102,316, this disclosure deals with the non-orbiting scroll member which is provided in the back thereof with a bushing device which is secured to a frame by means of bolts. The non-orbiting scroll member is capable of moving axially in conjunction with the bushing device. The axial displacement amount of the non-orbiting scroll member is determined by the difference the rim thickness of the non-orbiting scroll member and the height of the bushing device. In the meantime, the bottom of the nut serves as a locating surface. When the working media in the compression chamber has an abnormal pressure, the non-orbiting scroll member retreats to the locating surface so as to cause the formation of a gap between the orbiting and the non-orbiting scroll members for discharging the working media. The prior improvement is involved with fewer working elements. However, the non-orbiting scroll member is susceptible to being poorly located or being loosened unless the bushing device, the non-orbiting scroll member, and the frame are fastened together with precision. Moreover, an additional work must be done with the bottom of the nut, which serves as the locating surface. As a result, this prior art improvement is relative expensive.
Therefore, an invention devoting to resolving aforesaid disadvantages of conventional scroll machine in locating the scroll members is necessary, definitely.